Tumor deposits(TDs)are defined as discrete,irregular clusters of tumor cells lying in the soft tissue adjacent to but separate from the primary tumor,and are usually found in the lymphatic drainage area of the primary...Tumor deposits(TDs)are defined as discrete,irregular clusters of tumor cells lying in the soft tissue adjacent to but separate from the primary tumor,and are usually found in the lymphatic drainage area of the primary tumor.By definition,no residual lymph node structure should be identified in these tumor masses.At present,TDs are mainly reported in colorectal cancer,with a few reports in gastric cancer.There are very few reports on breast cancer(BC).For TDs,current dominant theories suggest that these are the result of lymph node metastasis of the tumor with complete destruction of the lymph nodes by the tumor tissue.Even some pathologists classify a TD as two lymph node metastases for calculation.Some pathologists also believe that TDs belong to the category of disseminated metastasis.Therefore,regardless of the origin,TDs are an indicator of poor prognosis.Moreover,for BC,sentinel lymph node biopsy is generally used at present.Whether radical axillary lymph node dissection should be adopted for BC with TDs in axillary lymph nodes is still inconclusive.The present commentary of this clinical issue has certain guiding significance.It is aimed to increase the awareness of the scientific community towards this under-recognized problem in BC pathology.展开更多
Collapsing erosion is a unique phenomenon commonly observed on the granite residue hillslopes in the tropical and subtropical regions of southern China,characterized by its abrupt occurrence and significant erosion vo...Collapsing erosion is a unique phenomenon commonly observed on the granite residue hillslopes in the tropical and subtropical regions of southern China,characterized by its abrupt occurrence and significant erosion volumes.However,the impacts of soil crust conditions on the erosion of colluvial deposits with granite residual soils have only been studied to a limited extent.To address this issue,this study investigates the impacts of three soil crust conditions(i.e.,without crust,10-minute crust,and 20-minute crust)on gully morphology,rainfall infiltration,and runoff and sediment yield during slope erosion of colluvial deposits with granite residues(classified as Acrisols)in Yudu County,Ganzhou City,Jiangxi Province,China,using simulated rainfall tests and photographic methods.The results showed that as the strength of the soil crust increased,the capacity of moisture infiltration and the width and depth of the gully as well as the sediment concentration and yield ratio decreased;at the same time,the runoff ratio increased.The sediment yield in the without-crust test was found to be 1.24 and 1.43 times higher than that observed in the 10-minute crust and 20-minute crust tests,respectively.These results indicate that soil crusts can effectively prevent slope erosion and moisture infiltration,while providing valuable insights for the management of soil erosion in natural environments.展开更多
Mississippi Valley-type(MVT) Zn-Pb deposits predominantly form within both orogenic forelands and fold-andthrust belts, yet the mineralization process within the latter tectonic setting remains inadequately understood...Mississippi Valley-type(MVT) Zn-Pb deposits predominantly form within both orogenic forelands and fold-andthrust belts, yet the mineralization process within the latter tectonic setting remains inadequately understood. This study, through a comprehensive review of MVT deposits across global fold-and-thrust belts, introduces a novel model elucidating the mineralization process in the context of tectonic belt evolution. It is demonstrated that during the stage Ⅰ, regional compression is introduced by early stages of plate convergence, causing the folding and thrusting and creating structural or lithological traps such as evaporite diapirs and unconformity-related carbonate dissolution-collapse structures. Thereafter, in stage Ⅱ, hydrocarbons begin to migrate and accumulate within these traps, where reduced sulfur is generated through thermochemical or bacterial sulfate reduction concurrent with or preceding Zn-Pb mineralization. In the subsequent stage Ⅲ, as plate convergence persists, the regional stress transitions from compression to transpression or extension. Under these conditions, steeply-dipping extensional faults are generated, facilitating the ascent of metalliferous brines into early-formed structural or lithological traps. Precipitation of Zn and Pb sulfides occurs through the mixing of Zn-Pb-transporting fluids with pre-existing reduced sulfur or by interaction with hydrocarbons.展开更多
Introduction The East Kunlun Orogenic Belt is located in the northeastern part of the Qinghai–Tibet Plateau(Li et al.,2007),stretching from the East Kunlun to the Elashan area in an east–west direction(Guo et al.,20...Introduction The East Kunlun Orogenic Belt is located in the northeastern part of the Qinghai–Tibet Plateau(Li et al.,2007),stretching from the East Kunlun to the Elashan area in an east–west direction(Guo et al.,2018).It is an important part of the Central Orogenic Belt(Xiong et al.,2023).It is considered one of the important gold mineralization regions in the Tethys tectonic domain(Norbu et al.,2023)and an essential potential base for mineral resources in China.Wulonggou and Gouli gold mines have been discovered successively,earning the reputation of the"Golden Belt of Qinghai Province"(Feng et al.,2004;He et al.,2023).展开更多
It is quite evident that it is not anomalous metal transport,nor unique depositional conditions,nor any single factor at the deposit scale,that dictates whether a mineral deposit becomes a giant or not.A hierarchical ...It is quite evident that it is not anomalous metal transport,nor unique depositional conditions,nor any single factor at the deposit scale,that dictates whether a mineral deposit becomes a giant or not.A hierarchical approach thus is required to progressively examine controlling parameters at successively decreasing scales in the total mineral system to understand the location of giant gold deposits in non-arc environments.For giant orogenic,intrusion-related gold systems(IRGS) and Carlin-type gold deposits and iron oxide-copper-gold(IOCG) deposits,there are common factors among all of these at the lithospheric to crustal scale.All are sited in giant gold provinces controlled by complex fundamental fault or shear zones that follow craton margins or,in the case of most Phanerozoic orogenic giants,define the primary suture zones between tectonic terranes.Giant provinces of IRGS,IOCG,and Carlin-type deposits require melting of metasomatized lithosphere beneath craton margins with ascent of hybrid lamprophyric to granitic magmas and associated heat flux to generate the giant province.The IRGS and IOCG deposits require direct exsolution of volatile-rich magmatic-hydrothermal fluids,whereas the association of such melts with Carlin-type ores is more indirect and enigmatic.Giant orogenic gold provinces show no direct relationship to such magmatism.forming from metamorphic fluids,but show an indirect relationship to lamprophyres that reflect the mantle connectivity of controlling first-order structures.In contrast to their province scale similarities,the different giant gold deposit styles show contrasting critical controls at the district to deposit scale.For orogenic gold deposits,the giants appear to have formed by conjunction of a greater number of parameters to those that control smaller deposits,with resultant geometrical and lithostratigraphic complexity as a guide to their location.There are few giant IRGS due to their inferior fluid-flux systems relative to orogenic gold deposits,and those few giants are essentially preservational exceptions.Many Carlin-type deposits are giants due to the exceptional conjunction of both structural and lithological parameters that caused reactive and permeable rocks,enriched in syngenetic gold,to be located below an impermeable cap along antiformal "trends".Hydrocarbons probably played an important role in concentrating metal.The supergiant Post-Betze deposit has additional ore zones in strain heterogeneities surrounding the pre-gold Goldstrike stock.All unequivocal IOCG deposits are giant or near-giant deposits in terms of gold-equivalent resources,partly due to economic factors for this relatively poorly understood,low Cu-Au grade deposit type.The supergiant Olympic Dam deposit,the most shallowly formed deposit among the larger IOCGs,probably owes its origin to eruption of volatile-rich hybrid magma at surface,with formation of a large maar and intense and widespread brecciation,alteration and Cu-Au-U deposition in a huge rock volume.展开更多
Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this...Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and deceleration.In the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up gradually.Deposits developed in the acceleration phase are reverse.In addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force.As a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin.In the erosion phase,the reverse deposits are eroded and become thinner or even disappear.Therefore,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the source.After entering the deceleration phase,normally grading deposits appear and cover previous deposits.The final deposits in the basin are special.Some are reverse,and others are normal.They are superimposed with each other under the action of hyperpycnal flow.The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of hyperpycnites.It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits.展开更多
The Jiadi and Damaidi gold deposits in southwest Guizhou Province are the largest basalt-hosted Carlintype gold deposits recently discovered in China.This study uses the Tescan Integrated Mineral Analyzer,supported by...The Jiadi and Damaidi gold deposits in southwest Guizhou Province are the largest basalt-hosted Carlintype gold deposits recently discovered in China.This study uses the Tescan Integrated Mineral Analyzer,supported by detailed field investigations,regional geological data,and extensive sample collections,including mineralized ore,altered wall rock,and unaltered basalt samples,for orebearing and geochemical analyses.Comparative analysis between altered and unaltered basalt samples revealed a mineral assemblage of sericite,quartz,and pyrite.This mineral composition forms through the hydrothermal alteration of unaltered basalt,originally containing feldspar,pyroxene,and ilmenite.The wall rock primarily features sericite,quartz,and hematite.During the alteration process,major,trace,and rare earth elements notably migrate.In the Jiadi deposit,K_(2)O,Rb,Au,and REE significantly increase,while Na_(2)O,CaO,MgO,and MnO decrease.SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3)levels remain relatively stable.In the Damaidi deposit,K_(2)O,Rb,and Au enrich,contrasting with the depletion of Na_(2)O,CaO,MgO,and MnO,while SiO_(2),Fe_(2)O_(3),Al_(2)O_(3),TiO_(2),and REE show no significant changes.In the wall rock,TiO_(2),Al_(2)O_(3),K_(2)O,and REE increase,while Na_(2)O,CaO,MgO,and MnO decrease;SiO_(2)and Fe_(2)O_(3)content remains unchanged.The mineralization process likely originated from mid-to low-temperature,reductive magmatic hydrothermal fluids rich in CO_(2),CH_(4),N_(2),H^(+),S^(2-),HS^(-),H_(3)AsO_(3),and[Au(HS_(2)]^(-).These fluids migrated to tectonically weak zones in the Lianhuashan area,where Emeishan basalts are present.They reacted with Fe-bearing minerals in the basalt,such as ferro-hornblende and ilmenite,forming pyrite,arsenic-bearing pyrite,and arsenopyrite,thus enriching Au in these minerals.Additionally,K^(+)and H^(+)in the fluid reacted with plagioclase in the basalt,forming sericite and quartz.As the fluid entered the wall rock from structural weak zones,its oxidation increased,leading to the complete or partial reaction of Fe-bearing minerals in the wall rock,resulting in the formation of hematite or magnetite.This mineralization process is similar to that observed in carbonate-hosted Carlin-type gold deposits in southwest Guizhou,with the primary distinction being the iron source.In carbonate deposits,iron originates from ferridolomite within the wall rock,while in basalt-hosted deposits,it derives from ferripyroxene and ilmenite.展开更多
In the sedimentary strata dating of estuarial coastal areas,it is often found that there is phenomenon of time-reversal in strata.The seabed sediments could be liquefied under storm waves.A laboratory wave flume exper...In the sedimentary strata dating of estuarial coastal areas,it is often found that there is phenomenon of time-reversal in strata.The seabed sediments could be liquefied under storm waves.A laboratory wave flume experiment demonstrated that storm-induced liquefaction deposits are formed by the oscillations of liquefied sediments.In this paper,the particle size distribution and ^(210)Pb_(ex) specific activity of the sediment samples from the liquefaction disturbed zone and adjacent stable zone of the Yellow River Delta were tested.The stratigraphic divisions based on storm liquefaction deposit sequence can effectively explain the vertical changes in particle size and ^(210)Pb_(ex) specific activity.Due to the differentiation of particles during the storm induced liquefaction,coarse and fine particles regrouped,which could explain the phenomenon of time-reversal in dating data.展开更多
Molybdenum is one of the dominant minerals in China because of its rich reserves.In recent years,outstanding breakthroughs have been made in molybdenum prospecting in China,and the distribution of molybdenum deposits ...Molybdenum is one of the dominant minerals in China because of its rich reserves.In recent years,outstanding breakthroughs have been made in molybdenum prospecting in China,and the distribution of molybdenum deposits in China is found to have a "planar pattern".In general,the molybdenum deposits are concentrated in eastern China,including the largest molybdenum reserves of Henan Province.In terms of the scale of molybdenum deposits,the identified resources of the superlarge deposits are the most important,which account for about 53% of the whole country,and those of the large deposits account for about 30%,those of the medium-sized deposits account for about 14%,those of the small-sized deposits,mine spots and mineralization account for about 3%.The molybdenum deposits are mainly classified as porphyry type,skarn type,hydrothermal(vein) type and sedimentary(metamorphic) type in genesis,and the identified resources of these types account for 85.75%,8.83%,2.79%and 2.63% of the total resources respectively.Based on the statistics of precise chronology data of molybdenites Re-Os,Mo-mineralization can be divided into 6 periods in Chinese geological history,which are Precambrian(〉800 Ma),Cambrian-Silurian(540-415 Ma,Caledonian),Devonian-Permian(400-290 Ma,Hecynian),Triassic(260-200 Ma,Indosinian),Jurassic-Cretaceous(195-70 Ma,Yanshanian) and Paleogene-Neogene(65-10 Ma,Himalayan).Mo mineralization during the Yanshanian period is the strongest one,in which about 76.69% of the Chinese total identified resources was formed.The second is the Himalayan period.According to spatial-temporal distribution characteristics of molybdenum deposits,the metallogenic regularity of molybdenum deposits was preliminarily summarized,and 41 level-Ⅲ molybdenum-forming belts,13 level-Ⅱ molybdenum-forming provinces and 4 level-Ⅰ molybdenum-forming domains were ascertained in the mainland of China.There are 39 metallogenic series of and 60 sub-series of molybdenum deposits with molybdenum as the dominant metal and corresponding representative molybdenum deposits proposed.Metallogenic lineages of molybdenum deposits were also established.Spatial-temporal evolution of different types of molybdenum deposits,and the relationship between Mo-mineralization and tectonic evolution have been discussed in this paper.On this basis,the authors think that element Mo is an effective tracer for recording the crustal evolution history of China.At present,there are some problems in the exploration of Mo deposits in China,such as uneven exploration degrees in eastern and western China,shallow exploration depth,low and uneven grade,complex associated components,difficulty of mineral development and utilization,increasing costs of prospecting,and so on.According to successful experience of superficial and deep prospecting and considering also the discussion above,some suggestions are proposed for the prospecting of molybdenum deposits in the future.展开更多
China is rich in tin resources,and contains many types of tin deposits.Among the tin deposit types,the cassiterite-sulfide type,skarn type and quartz vein type occupy a large proportion of tin resources and reserves.F...China is rich in tin resources,and contains many types of tin deposits.Among the tin deposit types,the cassiterite-sulfide type,skarn type and quartz vein type occupy a large proportion of tin resources and reserves.From the aspect of exploitation and utilization,the most important types are cassiterite-sulfide type and quartz vein type.The cassiterite-sulfide type tin deposits are mainly located in Northern Guangxi and Eastern Yunnan,skarn type deposits are mainly distributed in the ore-concentration areas of South Hunan in Middle Nanling,and the quartz vein type tin deposits are mainly distributed in South China,such as Western Fujian,Middle Jiangxi,Northern Guangzhou and Southern Hunan.The most important metallogenic epoch for tin deposits is the Mesozoic era.The metallogenic geotectonic background is mainly continental environments after orogeny process,with strong tectonic changes,interlaced deep fracture and frequent magmatism.And the most distinctive feature is the well developed Mesozoic granites,which have a close relationship with tin mineralization.Based on the detailed study of the data from 873 tin deposits in China,this paper summarized the metallogenic regularity of tin deposits,classified 20 important metallogenic series of tin or tin-associated deposits,and inferred that the cassiterite-sulfide type,skarn type,quartz vein type and greisen type are the main prediction types of tin resources.Forty-four tin-mineralization belts were divided,among which,19 belts are the most important.In addition,a series of maps about tin metallogenic belts and tin metallogenic regularity were compiled,aiming to provide theoretical basis for potential estimation and prediction of tin mineral resources.展开更多
This paper demonstrates the channels and methods for location prognosis of concealed ore deposits (bodies) in the deep seated and surrounding districts of productive mines in accordance with their special features. Th...This paper demonstrates the channels and methods for location prognosis of concealed ore deposits (bodies) in the deep seated and surrounding districts of productive mines in accordance with their special features. The system frame map is built, from quick exploration in the field to the rapid building of a model indoors. The main research points of location prognosis are also discussed in the paper, which include: 1) integrating the location with the surrounding geological areas, microscopic with macroscopic; 2) analyzing and synthesizing all geological information of different levels, depths and aspects; 3) laying stress on mineralization series; 4) paying attention to the study of the distribution law of ore bodies; 5) introducing the theory of nonlinear dynamics of ore forming processes to ordinary static prognosis; 6) the necessity of the geophysical me thod in recovering information of concealed ore bodies; 7) the combination of all kinds of geology, geophysics, geochemistry and remote sensing methods.展开更多
Intrusion-related gold deposits(IRGDs)occur in the Eastern Desert(ED)of Egypt within magmatic districts that are exploited for tungsten and tin mineralization.IRGDs and intrusion-related rare metal deposits(IRRMDs)are...Intrusion-related gold deposits(IRGDs)occur in the Eastern Desert(ED)of Egypt within magmatic districts that are exploited for tungsten and tin mineralization.IRGDs and intrusion-related rare metal deposits(IRRMDs)are almost invariably linked with the late to post collisional Younger Granites(YGs)that have three successive phases(Ⅰ,ⅡandⅢ).At~635–630 Ma,the ED underwent a transition in deformation style from compressional to extensional and a switch from subduction with crustal thickening to delamination with crustal thinning.This transition was concurrent with the emplacement of a short magmatic pulse(~635–630 Ma)that represents a transition between orogenic gold deposits and IRGDs.K-rich calc alkaline granites(phaseⅠandⅡof the YGs)hosting IRGDs like the Hangalia deposit were emplaced during the time span 630–610 Ma.Alkaline magmatism began at 610 Ma,coexisting with the K-rich calc-alkaline magmatism over the 610–590 Ma time span,where the Fawakhir(598±3 Ma)and Um Had(596±2 Ma)granites that host the IRGDs were emplaced.In time,the alkaline magmatism became more alkaline giving rise to phaseⅢof the YGs that hosts IRRMDs.A distinct metallogenic epoch comprising both IRGDs and IRRMDs,was undergoing extreme growth at~600 Ma.展开更多
China's realgar/orpiment deposits may be classified into three types, the stratabound, hot-water sedimentary and hydrothermal, according to their mineralizing processes, geological occurrences, tectonic and geoche...China's realgar/orpiment deposits may be classified into three types, the stratabound, hot-water sedimentary and hydrothermal, according to their mineralizing processes, geological occurrences, tectonic and geochemical features. The three types may be further distinguished into seven subtypes, namely, the Xiaguan, Shuiluo, Jiepaiyu, Songpan, Shixia, Wangzhuang and Ninghshan ones. On this basis three minerogenic models are established, and based on studies of their geochemistry and minerogenic mechanisms the prerequisites for prospecting for these types of deposits are given in the paper.展开更多
Identification and quantitative prediction of large and superlarge mineral deposits of solid mineral resources using the mineral resource prediction theory and method with comprehensive information is carried out nati...Identification and quantitative prediction of large and superlarge mineral deposits of solid mineral resources using the mineral resource prediction theory and method with comprehensive information is carried out nationwide in China at a scale of 1∶5 000 000. Using deposit concentrated regions as the model units and concentrated mineralization anomaly regions as prediction units, the prediction is performed on GIS platform. The technical route and research method of locating large and superlarge mineral deposits and principle of compiling attribute table of independent variables and functional variables are proposed. Upon methodology study, the qualitative locating and quantitative predicting mineral deposits are carried out with quantitative theory Ⅲ and characteristic analysis, respectively, and the advantage and disadvantage of two methods are discussed. This research is significant for mineral resource prediction in ten provinces of western China.展开更多
The cleanliness of gasoline is related to its components and properties.All commercial gasoline builds up deposits on the engine's injector,intake valve and combustion chamber,which can significantly lower the eng...The cleanliness of gasoline is related to its components and properties.All commercial gasoline builds up deposits on the engine's injector,intake valve and combustion chamber,which can significantly lower the engine performance and influence exhaust gas emissions.In this study,the intake valve deposits (IVD) and combustion chamber deposits (CCD) produced from combustion of fuel containing 21 v%—42 v% of aromatics and 8 v%—31 v% of olefins have been studied using Ford engine tests,and the characteristics of deposits were studied by IR spectroscopy,TGA and elemental analysis instrument.The test results have shown that deposit formation depends on the fuel composition,especially the aromatic content in the fuel.It is also observed that there are differences in the values of IVD and CCD measured by IR spectrometry and elemental analyses.展开更多
Nonferrous mining activities are some of the largest sources of heavy metals emissions into the environment and China is one of the largest producers and consumers of lead and zinc in the world.The cumulative producti...Nonferrous mining activities are some of the largest sources of heavy metals emissions into the environment and China is one of the largest producers and consumers of lead and zinc in the world.The cumulative productions and emissions of lead and zinc from mining-related activities in China were estimated.Up to 2007,the cumulative productions of lead and zinc in China were estimated to be about 6.69 and 12.59 Mt,respectively;and about 1.62 Mt lead and 3.32 Mt zinc emitted into the ambient environment during the mining,processing and smelting activities,representing 24.39% and 26.36% cumulative production,respectively.Among these three types of mining-related activities,mineral processing contributes the most to the total emission of 50.67% lead and 45.51% zinc.展开更多
Acoupled biharmonic spline and linear interpolation algorithm was proposed to create a three-dimensional smooth deposit model with minimal curvature containing grade and position data. To obtain the optimal technical ...Acoupled biharmonic spline and linear interpolation algorithm was proposed to create a three-dimensional smooth deposit model with minimal curvature containing grade and position data. To obtain the optimal technical parameters, such as cuttingheight and drum diameter, a virtual longwall mining procedure was modelled by simulating the actual fully mechanized longwall mining process. Based on the above work, a bauxite deposit in a longwall mining panel was modelled by scattered grade data from ores sampled on the entry wall. The deposit was then demarcated by industrial indexes and sliced according to the virtual longwallmining procedure. The results show that the proposed interpolation algorithm can depict the stratiform structure of bauxite depositsand that the uncovered bauxite deposit has high proportions of high-grade and rich ore. The ranges of optimal cutting height and drum diameters are 1.72-2.84 m and 1.42-1.72 m, respectively. Finally, an intellectualized longwall mining procedure was designed to guide the mining process with the lowest dilution and loss rates.展开更多
The world-class Huize Pb-Zn deposits of Yunnan province,in southwestern China,located in the center of the Sichuan-Yunnan-Guizhou Pb-Zn polymetallic metallogenic province,has Pb+Zn reserves of more than 5 million ton...The world-class Huize Pb-Zn deposits of Yunnan province,in southwestern China,located in the center of the Sichuan-Yunnan-Guizhou Pb-Zn polymetallic metallogenic province,has Pb+Zn reserves of more than 5 million tons at Pb+Zn grade of higher than 25%and contains abundant associated metals,such as Ag,Ge,Cd,and Ga.The deposits are hosted in the Lower Carboniferous carbonate strata and the Permian Emeishan basalts which distributed in the northern and southwestern parts of the orefield.Calcite is the only gangue mineral in the primary ores of the deposits and can be classified into three types,namely lumpy,patch and vein calcites in accordance with their occurrence.There is not intercalated contact between calcite and ore minerals and among the three types of calcite,indicating that they are the same ore-forming age with different stages and its forming sequence is from lumpy to patch to vein calcites. This paper presents the rare earth element(REE) and C-O isotopic compositions of calcites in the Huize Pb-Zn deposits.From lumpy to patch to vein calcites,REE contents decrease as LREE/ HREE ratios increase.The chondrite-normalized REE patterns of the three types of calcites are characterized by LREE-rich shaped,in which the lumpy calcite shows(La)_N〈(Ce)_N〈(Pr)_N≈(Nd)_N with Eu/Eu~*〈1,the patch calcite has(La)_N〈(Ce)_N〈(Pr)_N≈(Nd)_N with Eu/Eu~*〉1,and the vein calcite displays(La)_N〉(Ce)_N〉(Pr)_N〉(Nd)_N with Eu/Eu~*〉1.The REE geochemistry of the three types of calcite is different from those of the strata of various age and Permian Emeishan basalt exposed in the orefield.Theδ^(13) C_(PDb) andδ^(18)O_(Smow) values of the three types of calcites vary from-3.5‰to-2.1‰and 16.7‰to 18.6‰,respectively,falling within a small field between primary mantle and marine carbonate in theδ^(13)C_(PDb) vsδ^(18)O_(Smow) diagram. Various lines of evidence demonstrate that the three types of calcites in the deposits are produced from the same source with different stages.The ore-forming fluids of the deposits resulted from crustal -mantle mixing processes,in which the mantle-derived fluid components might be formed from degassing of mantle or/and magmatism of the Permian Emeishan basalts,and the crustal fluid was mainly provided by carbonate strata in the orefield.The ore-forming fluids in the deposits were homogenized before mineralization,and the ore-forming environment varied from relatively reducing to oxidizing.展开更多
The western margin of Yangtze Craton is known as a significant sediment-hosted base-metal aggregate cluster,especially for Pb-Zn deposits in China,e.g.Jinding,Daliangzi,Tianbaoshan, Kuangshanchang and Qinlinchang depo...The western margin of Yangtze Craton is known as a significant sediment-hosted base-metal aggregate cluster,especially for Pb-Zn deposits in China,e.g.Jinding,Daliangzi,Tianbaoshan, Kuangshanchang and Qinlinchang deposits.In comparison with the classic MVT deposits in the world, based on the basic geology of the sediment-hosted Pb-Zn deposits,this paper focuses on temporal-spatial distribution of this deposit to further discuss its large scale mineralization and tectonic evolution history.In the SW Sanjiang Thethys,Jinding deposit is typically thrust fault-controlled and hosted mainly in the sandstones and breccia-bearing sandstones,whereas MVT-type deposits are controlled by lithology and faulting/fracturing with a strong preference for carbonate-hosted rocks.Most importantly,Jinding Pb-Zn deposit differs from the other types of sediment-hosted Pb-Zn deposits in which it was formed in a strongly deformed foreland basin within a continental collision zone.In the Kangdian area,the sediment-hosted Pb-Zn deposits were formed in the extensional basin on the side of the continental orogenic belt along the Yangtze Craton.Compared with classic MVT deposits,the Pb-Zn deposits in the Kangdian area belong to MVT deposits.This paper is significant not only for interpretation of the genesis of sediment-hosted Pb-Zn deposits but also for exploiting large base metal deposits in large sedimentary target areas.展开更多
Seventy-three large-superlarge deposits in China were formed in 4 metallogenic epochs, and located in 6 metallogenic domains. By combing their time-space distribution and the relevant data of crustal thickness, we dis...Seventy-three large-superlarge deposits in China were formed in 4 metallogenic epochs, and located in 6 metallogenic domains. By combing their time-space distribution and the relevant data of crustal thickness, we discuss the control conditions of deep tectonics on superlarge deposits. The various spatial variation of the crustal thickness where deposits locate is closely related to their different tectonic setting. The crustal thickness of the region where deposits are in the Precatnbrian metallogenic epoch is 37.1 km and shows double-peak distribution, which is related to the different tectonic-mineralization processes in the Tarim-North China and Yangtze metallogenic domains. The crustal thickness of the region where deposits are in the Paleoproterozoic metallogenic epoch is 43.4 km and shows normal distribution, which is the result of 'pure' mineralization setting. The crustal thickness of the region where deposits are in the Late Palaeozoic-Early Mesozoic metallogenic epoch is about 41.2 km and shows multi-peak distribution, which can be related with dispersing distribution in the metallogenic domain of these superlarge deposits. The crustal thickness of the region where deposits are in the post-Indosinian metallogenic epoch is 37.3 km, and shows skew distribution, which resulted from different tectonic settings in eastern and western China.展开更多
文摘Tumor deposits(TDs)are defined as discrete,irregular clusters of tumor cells lying in the soft tissue adjacent to but separate from the primary tumor,and are usually found in the lymphatic drainage area of the primary tumor.By definition,no residual lymph node structure should be identified in these tumor masses.At present,TDs are mainly reported in colorectal cancer,with a few reports in gastric cancer.There are very few reports on breast cancer(BC).For TDs,current dominant theories suggest that these are the result of lymph node metastasis of the tumor with complete destruction of the lymph nodes by the tumor tissue.Even some pathologists classify a TD as two lymph node metastases for calculation.Some pathologists also believe that TDs belong to the category of disseminated metastasis.Therefore,regardless of the origin,TDs are an indicator of poor prognosis.Moreover,for BC,sentinel lymph node biopsy is generally used at present.Whether radical axillary lymph node dissection should be adopted for BC with TDs in axillary lymph nodes is still inconclusive.The present commentary of this clinical issue has certain guiding significance.It is aimed to increase the awareness of the scientific community towards this under-recognized problem in BC pathology.
基金This work was supported by the National Natural Science Foundation of China[Grant Nos.41962015,52208348]the Jiangxi Provincial Natural Science Foundation[Grant No.20224BAB214064,20232BAB204083].
文摘Collapsing erosion is a unique phenomenon commonly observed on the granite residue hillslopes in the tropical and subtropical regions of southern China,characterized by its abrupt occurrence and significant erosion volumes.However,the impacts of soil crust conditions on the erosion of colluvial deposits with granite residual soils have only been studied to a limited extent.To address this issue,this study investigates the impacts of three soil crust conditions(i.e.,without crust,10-minute crust,and 20-minute crust)on gully morphology,rainfall infiltration,and runoff and sediment yield during slope erosion of colluvial deposits with granite residues(classified as Acrisols)in Yudu County,Ganzhou City,Jiangxi Province,China,using simulated rainfall tests and photographic methods.The results showed that as the strength of the soil crust increased,the capacity of moisture infiltration and the width and depth of the gully as well as the sediment concentration and yield ratio decreased;at the same time,the runoff ratio increased.The sediment yield in the without-crust test was found to be 1.24 and 1.43 times higher than that observed in the 10-minute crust and 20-minute crust tests,respectively.These results indicate that soil crusts can effectively prevent slope erosion and moisture infiltration,while providing valuable insights for the management of soil erosion in natural environments.
基金funded by National Natural Science Foundation of China (Grant Nos. 42125204, 92155305, 42103068, 42372114, 42372115)。
文摘Mississippi Valley-type(MVT) Zn-Pb deposits predominantly form within both orogenic forelands and fold-andthrust belts, yet the mineralization process within the latter tectonic setting remains inadequately understood. This study, through a comprehensive review of MVT deposits across global fold-and-thrust belts, introduces a novel model elucidating the mineralization process in the context of tectonic belt evolution. It is demonstrated that during the stage Ⅰ, regional compression is introduced by early stages of plate convergence, causing the folding and thrusting and creating structural or lithological traps such as evaporite diapirs and unconformity-related carbonate dissolution-collapse structures. Thereafter, in stage Ⅱ, hydrocarbons begin to migrate and accumulate within these traps, where reduced sulfur is generated through thermochemical or bacterial sulfate reduction concurrent with or preceding Zn-Pb mineralization. In the subsequent stage Ⅲ, as plate convergence persists, the regional stress transitions from compression to transpression or extension. Under these conditions, steeply-dipping extensional faults are generated, facilitating the ascent of metalliferous brines into early-formed structural or lithological traps. Precipitation of Zn and Pb sulfides occurs through the mixing of Zn-Pb-transporting fluids with pre-existing reduced sulfur or by interaction with hydrocarbons.
基金supported by Qinghai Provincial Association for Science and Technology Youth Science and Technology Talent Support Project(Grant No.2023QHSKXRCTJ47)Exploration Foundation of Qinghai Province(Grant No.2023085029ky004)。
文摘Introduction The East Kunlun Orogenic Belt is located in the northeastern part of the Qinghai–Tibet Plateau(Li et al.,2007),stretching from the East Kunlun to the Elashan area in an east–west direction(Guo et al.,2018).It is an important part of the Central Orogenic Belt(Xiong et al.,2023).It is considered one of the important gold mineralization regions in the Tethys tectonic domain(Norbu et al.,2023)and an essential potential base for mineral resources in China.Wulonggou and Gouli gold mines have been discovered successively,earning the reputation of the"Golden Belt of Qinghai Province"(Feng et al.,2004;He et al.,2023).
基金funded by Talent Award under the 1000 Plan Project from the Chinese Government
文摘It is quite evident that it is not anomalous metal transport,nor unique depositional conditions,nor any single factor at the deposit scale,that dictates whether a mineral deposit becomes a giant or not.A hierarchical approach thus is required to progressively examine controlling parameters at successively decreasing scales in the total mineral system to understand the location of giant gold deposits in non-arc environments.For giant orogenic,intrusion-related gold systems(IRGS) and Carlin-type gold deposits and iron oxide-copper-gold(IOCG) deposits,there are common factors among all of these at the lithospheric to crustal scale.All are sited in giant gold provinces controlled by complex fundamental fault or shear zones that follow craton margins or,in the case of most Phanerozoic orogenic giants,define the primary suture zones between tectonic terranes.Giant provinces of IRGS,IOCG,and Carlin-type deposits require melting of metasomatized lithosphere beneath craton margins with ascent of hybrid lamprophyric to granitic magmas and associated heat flux to generate the giant province.The IRGS and IOCG deposits require direct exsolution of volatile-rich magmatic-hydrothermal fluids,whereas the association of such melts with Carlin-type ores is more indirect and enigmatic.Giant orogenic gold provinces show no direct relationship to such magmatism.forming from metamorphic fluids,but show an indirect relationship to lamprophyres that reflect the mantle connectivity of controlling first-order structures.In contrast to their province scale similarities,the different giant gold deposit styles show contrasting critical controls at the district to deposit scale.For orogenic gold deposits,the giants appear to have formed by conjunction of a greater number of parameters to those that control smaller deposits,with resultant geometrical and lithostratigraphic complexity as a guide to their location.There are few giant IRGS due to their inferior fluid-flux systems relative to orogenic gold deposits,and those few giants are essentially preservational exceptions.Many Carlin-type deposits are giants due to the exceptional conjunction of both structural and lithological parameters that caused reactive and permeable rocks,enriched in syngenetic gold,to be located below an impermeable cap along antiformal "trends".Hydrocarbons probably played an important role in concentrating metal.The supergiant Post-Betze deposit has additional ore zones in strain heterogeneities surrounding the pre-gold Goldstrike stock.All unequivocal IOCG deposits are giant or near-giant deposits in terms of gold-equivalent resources,partly due to economic factors for this relatively poorly understood,low Cu-Au grade deposit type.The supergiant Olympic Dam deposit,the most shallowly formed deposit among the larger IOCGs,probably owes its origin to eruption of volatile-rich hybrid magma at surface,with formation of a large maar and intense and widespread brecciation,alteration and Cu-Au-U deposition in a huge rock volume.
基金the Scientific research and technology development project of Petro China(2021DJ5303)。
文摘Sedimentary process research is of great significance for understanding the distribution and characteristics of sediments.Through the detailed observation and measurement of the Sangyuan outcrop in Luanping Basin,this paper studies the depositional process of the hyperpycnal flow deposits,and divides their depositional process into three phases,namely,acceleration,erosion and deceleration.In the acceleration phase,hyperpycnal flow begins to enter the basin nearby,and then speeds up gradually.Deposits developed in the acceleration phase are reverse.In addition,the original deposits become unstable and are taken away by hyperpycnal flows under the eroding force.As a result,there are a lot of mixture of red mud pebbles outside the basin and gray mud pebbles within the basin.In the erosion phase,the reverse deposits are eroded and become thinner or even disappear.Therefore,no reverse grading characteristic is found in the proximal major channel that is closer to the source,but it is still preserved in the middle branch channel that is far from the source.After entering the deceleration phase,normally grading deposits appear and cover previous deposits.The final deposits in the basin are special.Some are reverse,and others are normal.They are superimposed with each other under the action of hyperpycnal flow.The analysis of the Sangyuan outcrop demonstrates the sedimentary process and distribution of hyperpycnites,and reasonably explain the sedimentary characteristics of hyperpycnites.It is helpful to the prediction of oil and gas exploration targets in gravity flow deposits.
基金funded by the Talent Team Program of Science and Technology Foundation of Guizhou Province(CXTD[2021]007)the Key Project of Natural Science Basic Research Program of Shannxi Province(2023-JC-ZD-16)+4 种基金the National Natural Science Fund of China(U1812402)the National Natural Science Fund of China(41962008)the National Key Research and Development Program of China“Exploration and Exploitation of Deep Earth Resources”(2017YFC0601500)the Guizhou Province Graduate Research Fund(YJSCXJH[2020]095)the public welfare and fundamental project Fund of Guizhou Province(520000214 TLCOG7DGTNRG)。
文摘The Jiadi and Damaidi gold deposits in southwest Guizhou Province are the largest basalt-hosted Carlintype gold deposits recently discovered in China.This study uses the Tescan Integrated Mineral Analyzer,supported by detailed field investigations,regional geological data,and extensive sample collections,including mineralized ore,altered wall rock,and unaltered basalt samples,for orebearing and geochemical analyses.Comparative analysis between altered and unaltered basalt samples revealed a mineral assemblage of sericite,quartz,and pyrite.This mineral composition forms through the hydrothermal alteration of unaltered basalt,originally containing feldspar,pyroxene,and ilmenite.The wall rock primarily features sericite,quartz,and hematite.During the alteration process,major,trace,and rare earth elements notably migrate.In the Jiadi deposit,K_(2)O,Rb,Au,and REE significantly increase,while Na_(2)O,CaO,MgO,and MnO decrease.SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3)levels remain relatively stable.In the Damaidi deposit,K_(2)O,Rb,and Au enrich,contrasting with the depletion of Na_(2)O,CaO,MgO,and MnO,while SiO_(2),Fe_(2)O_(3),Al_(2)O_(3),TiO_(2),and REE show no significant changes.In the wall rock,TiO_(2),Al_(2)O_(3),K_(2)O,and REE increase,while Na_(2)O,CaO,MgO,and MnO decrease;SiO_(2)and Fe_(2)O_(3)content remains unchanged.The mineralization process likely originated from mid-to low-temperature,reductive magmatic hydrothermal fluids rich in CO_(2),CH_(4),N_(2),H^(+),S^(2-),HS^(-),H_(3)AsO_(3),and[Au(HS_(2)]^(-).These fluids migrated to tectonically weak zones in the Lianhuashan area,where Emeishan basalts are present.They reacted with Fe-bearing minerals in the basalt,such as ferro-hornblende and ilmenite,forming pyrite,arsenic-bearing pyrite,and arsenopyrite,thus enriching Au in these minerals.Additionally,K^(+)and H^(+)in the fluid reacted with plagioclase in the basalt,forming sericite and quartz.As the fluid entered the wall rock from structural weak zones,its oxidation increased,leading to the complete or partial reaction of Fe-bearing minerals in the wall rock,resulting in the formation of hematite or magnetite.This mineralization process is similar to that observed in carbonate-hosted Carlin-type gold deposits in southwest Guizhou,with the primary distinction being the iron source.In carbonate deposits,iron originates from ferridolomite within the wall rock,while in basalt-hosted deposits,it derives from ferripyroxene and ilmenite.
基金funding for this project was provided by the National Natural Science Foundation of China (No.41976049)。
文摘In the sedimentary strata dating of estuarial coastal areas,it is often found that there is phenomenon of time-reversal in strata.The seabed sediments could be liquefied under storm waves.A laboratory wave flume experiment demonstrated that storm-induced liquefaction deposits are formed by the oscillations of liquefied sediments.In this paper,the particle size distribution and ^(210)Pb_(ex) specific activity of the sediment samples from the liquefaction disturbed zone and adjacent stable zone of the Yellow River Delta were tested.The stratigraphic divisions based on storm liquefaction deposit sequence can effectively explain the vertical changes in particle size and ^(210)Pb_(ex) specific activity.Due to the differentiation of particles during the storm induced liquefaction,coarse and fine particles regrouped,which could explain the phenomenon of time-reversal in dating data.
基金funded by the National Natural Science Fund for Youth(Grant No.41402069)Scientific Research Fund of the China Central Non-Commercial Institute(Grant No.1305,K1022 and K1001)+1 种基金Geological Survey Program of comprehensive study of Chinese mineral geology and regional metallogenic regularity (Grant No.12120114039701,12120114039601)mineral resources potential evaluation(Grant No. 1212010633901)
文摘Molybdenum is one of the dominant minerals in China because of its rich reserves.In recent years,outstanding breakthroughs have been made in molybdenum prospecting in China,and the distribution of molybdenum deposits in China is found to have a "planar pattern".In general,the molybdenum deposits are concentrated in eastern China,including the largest molybdenum reserves of Henan Province.In terms of the scale of molybdenum deposits,the identified resources of the superlarge deposits are the most important,which account for about 53% of the whole country,and those of the large deposits account for about 30%,those of the medium-sized deposits account for about 14%,those of the small-sized deposits,mine spots and mineralization account for about 3%.The molybdenum deposits are mainly classified as porphyry type,skarn type,hydrothermal(vein) type and sedimentary(metamorphic) type in genesis,and the identified resources of these types account for 85.75%,8.83%,2.79%and 2.63% of the total resources respectively.Based on the statistics of precise chronology data of molybdenites Re-Os,Mo-mineralization can be divided into 6 periods in Chinese geological history,which are Precambrian(〉800 Ma),Cambrian-Silurian(540-415 Ma,Caledonian),Devonian-Permian(400-290 Ma,Hecynian),Triassic(260-200 Ma,Indosinian),Jurassic-Cretaceous(195-70 Ma,Yanshanian) and Paleogene-Neogene(65-10 Ma,Himalayan).Mo mineralization during the Yanshanian period is the strongest one,in which about 76.69% of the Chinese total identified resources was formed.The second is the Himalayan period.According to spatial-temporal distribution characteristics of molybdenum deposits,the metallogenic regularity of molybdenum deposits was preliminarily summarized,and 41 level-Ⅲ molybdenum-forming belts,13 level-Ⅱ molybdenum-forming provinces and 4 level-Ⅰ molybdenum-forming domains were ascertained in the mainland of China.There are 39 metallogenic series of and 60 sub-series of molybdenum deposits with molybdenum as the dominant metal and corresponding representative molybdenum deposits proposed.Metallogenic lineages of molybdenum deposits were also established.Spatial-temporal evolution of different types of molybdenum deposits,and the relationship between Mo-mineralization and tectonic evolution have been discussed in this paper.On this basis,the authors think that element Mo is an effective tracer for recording the crustal evolution history of China.At present,there are some problems in the exploration of Mo deposits in China,such as uneven exploration degrees in eastern and western China,shallow exploration depth,low and uneven grade,complex associated components,difficulty of mineral development and utilization,increasing costs of prospecting,and so on.According to successful experience of superficial and deep prospecting and considering also the discussion above,some suggestions are proposed for the prospecting of molybdenum deposits in the future.
基金supported by the National Natural Science Foundation(grant No.41202025,41302058)Funds on basic researches for central public welfare academic institutes(grant No.K1325 and YK1401)the China Geological Survey Project(Nos.1212011220369, 1212010633903,12120114039601 and 12120114019401)
文摘China is rich in tin resources,and contains many types of tin deposits.Among the tin deposit types,the cassiterite-sulfide type,skarn type and quartz vein type occupy a large proportion of tin resources and reserves.From the aspect of exploitation and utilization,the most important types are cassiterite-sulfide type and quartz vein type.The cassiterite-sulfide type tin deposits are mainly located in Northern Guangxi and Eastern Yunnan,skarn type deposits are mainly distributed in the ore-concentration areas of South Hunan in Middle Nanling,and the quartz vein type tin deposits are mainly distributed in South China,such as Western Fujian,Middle Jiangxi,Northern Guangzhou and Southern Hunan.The most important metallogenic epoch for tin deposits is the Mesozoic era.The metallogenic geotectonic background is mainly continental environments after orogeny process,with strong tectonic changes,interlaced deep fracture and frequent magmatism.And the most distinctive feature is the well developed Mesozoic granites,which have a close relationship with tin mineralization.Based on the detailed study of the data from 873 tin deposits in China,this paper summarized the metallogenic regularity of tin deposits,classified 20 important metallogenic series of tin or tin-associated deposits,and inferred that the cassiterite-sulfide type,skarn type,quartz vein type and greisen type are the main prediction types of tin resources.Forty-four tin-mineralization belts were divided,among which,19 belts are the most important.In addition,a series of maps about tin metallogenic belts and tin metallogenic regularity were compiled,aiming to provide theoretical basis for potential estimation and prediction of tin mineral resources.
文摘This paper demonstrates the channels and methods for location prognosis of concealed ore deposits (bodies) in the deep seated and surrounding districts of productive mines in accordance with their special features. The system frame map is built, from quick exploration in the field to the rapid building of a model indoors. The main research points of location prognosis are also discussed in the paper, which include: 1) integrating the location with the surrounding geological areas, microscopic with macroscopic; 2) analyzing and synthesizing all geological information of different levels, depths and aspects; 3) laying stress on mineralization series; 4) paying attention to the study of the distribution law of ore bodies; 5) introducing the theory of nonlinear dynamics of ore forming processes to ordinary static prognosis; 6) the necessity of the geophysical me thod in recovering information of concealed ore bodies; 7) the combination of all kinds of geology, geophysics, geochemistry and remote sensing methods.
文摘Intrusion-related gold deposits(IRGDs)occur in the Eastern Desert(ED)of Egypt within magmatic districts that are exploited for tungsten and tin mineralization.IRGDs and intrusion-related rare metal deposits(IRRMDs)are almost invariably linked with the late to post collisional Younger Granites(YGs)that have three successive phases(Ⅰ,ⅡandⅢ).At~635–630 Ma,the ED underwent a transition in deformation style from compressional to extensional and a switch from subduction with crustal thickening to delamination with crustal thinning.This transition was concurrent with the emplacement of a short magmatic pulse(~635–630 Ma)that represents a transition between orogenic gold deposits and IRGDs.K-rich calc alkaline granites(phaseⅠandⅡof the YGs)hosting IRGDs like the Hangalia deposit were emplaced during the time span 630–610 Ma.Alkaline magmatism began at 610 Ma,coexisting with the K-rich calc-alkaline magmatism over the 610–590 Ma time span,where the Fawakhir(598±3 Ma)and Um Had(596±2 Ma)granites that host the IRGDs were emplaced.In time,the alkaline magmatism became more alkaline giving rise to phaseⅢof the YGs that hosts IRRMDs.A distinct metallogenic epoch comprising both IRGDs and IRRMDs,was undergoing extreme growth at~600 Ma.
文摘China's realgar/orpiment deposits may be classified into three types, the stratabound, hot-water sedimentary and hydrothermal, according to their mineralizing processes, geological occurrences, tectonic and geochemical features. The three types may be further distinguished into seven subtypes, namely, the Xiaguan, Shuiluo, Jiepaiyu, Songpan, Shixia, Wangzhuang and Ninghshan ones. On this basis three minerogenic models are established, and based on studies of their geochemistry and minerogenic mechanisms the prerequisites for prospecting for these types of deposits are given in the paper.
文摘Identification and quantitative prediction of large and superlarge mineral deposits of solid mineral resources using the mineral resource prediction theory and method with comprehensive information is carried out nationwide in China at a scale of 1∶5 000 000. Using deposit concentrated regions as the model units and concentrated mineralization anomaly regions as prediction units, the prediction is performed on GIS platform. The technical route and research method of locating large and superlarge mineral deposits and principle of compiling attribute table of independent variables and functional variables are proposed. Upon methodology study, the qualitative locating and quantitative predicting mineral deposits are carried out with quantitative theory Ⅲ and characteristic analysis, respectively, and the advantage and disadvantage of two methods are discussed. This research is significant for mineral resource prediction in ten provinces of western China.
基金the PetroChina Corporation Research and Development Project (06-03B-01-01) for financial support
文摘The cleanliness of gasoline is related to its components and properties.All commercial gasoline builds up deposits on the engine's injector,intake valve and combustion chamber,which can significantly lower the engine performance and influence exhaust gas emissions.In this study,the intake valve deposits (IVD) and combustion chamber deposits (CCD) produced from combustion of fuel containing 21 v%—42 v% of aromatics and 8 v%—31 v% of olefins have been studied using Ford engine tests,and the characteristics of deposits were studied by IR spectroscopy,TGA and elemental analysis instrument.The test results have shown that deposit formation depends on the fuel composition,especially the aromatic content in the fuel.It is also observed that there are differences in the values of IVD and CCD measured by IR spectrometry and elemental analyses.
基金Project (2007BAC03A11-07) supported by the Ministry of Science and Technology of ChinaProject (KZCX3-SW-437) supported by the Chinese Academy of SciencesProjects (41040014,40571008) supported by the National Natural Science Foundation of China
文摘Nonferrous mining activities are some of the largest sources of heavy metals emissions into the environment and China is one of the largest producers and consumers of lead and zinc in the world.The cumulative productions and emissions of lead and zinc from mining-related activities in China were estimated.Up to 2007,the cumulative productions of lead and zinc in China were estimated to be about 6.69 and 12.59 Mt,respectively;and about 1.62 Mt lead and 3.32 Mt zinc emitted into the ambient environment during the mining,processing and smelting activities,representing 24.39% and 26.36% cumulative production,respectively.Among these three types of mining-related activities,mineral processing contributes the most to the total emission of 50.67% lead and 45.51% zinc.
基金Project(11472311)supported by the National Natural Science Foundation of ChinaProject(2015CX005)supported by the Innovation Driven Plan of Central South University of ChinaProject(2015zzts083)supported by the Fundamental Research Funds for the Central Universities of Central South University,China
文摘Acoupled biharmonic spline and linear interpolation algorithm was proposed to create a three-dimensional smooth deposit model with minimal curvature containing grade and position data. To obtain the optimal technical parameters, such as cuttingheight and drum diameter, a virtual longwall mining procedure was modelled by simulating the actual fully mechanized longwall mining process. Based on the above work, a bauxite deposit in a longwall mining panel was modelled by scattered grade data from ores sampled on the entry wall. The deposit was then demarcated by industrial indexes and sliced according to the virtual longwallmining procedure. The results show that the proposed interpolation algorithm can depict the stratiform structure of bauxite depositsand that the uncovered bauxite deposit has high proportions of high-grade and rich ore. The ranges of optimal cutting height and drum diameters are 1.72-2.84 m and 1.42-1.72 m, respectively. Finally, an intellectualized longwall mining procedure was designed to guide the mining process with the lowest dilution and loss rates.
基金jointly by National Basic Research Program of China(973 Program) (2007CB411402)the Knowledge innovation project of Chinese Academy of Sciences(KZCX2-YW-Q04-05, KZCX2-YW-111-03)the National Natural Science Foundation of China(No.40573036).
文摘The world-class Huize Pb-Zn deposits of Yunnan province,in southwestern China,located in the center of the Sichuan-Yunnan-Guizhou Pb-Zn polymetallic metallogenic province,has Pb+Zn reserves of more than 5 million tons at Pb+Zn grade of higher than 25%and contains abundant associated metals,such as Ag,Ge,Cd,and Ga.The deposits are hosted in the Lower Carboniferous carbonate strata and the Permian Emeishan basalts which distributed in the northern and southwestern parts of the orefield.Calcite is the only gangue mineral in the primary ores of the deposits and can be classified into three types,namely lumpy,patch and vein calcites in accordance with their occurrence.There is not intercalated contact between calcite and ore minerals and among the three types of calcite,indicating that they are the same ore-forming age with different stages and its forming sequence is from lumpy to patch to vein calcites. This paper presents the rare earth element(REE) and C-O isotopic compositions of calcites in the Huize Pb-Zn deposits.From lumpy to patch to vein calcites,REE contents decrease as LREE/ HREE ratios increase.The chondrite-normalized REE patterns of the three types of calcites are characterized by LREE-rich shaped,in which the lumpy calcite shows(La)_N〈(Ce)_N〈(Pr)_N≈(Nd)_N with Eu/Eu~*〈1,the patch calcite has(La)_N〈(Ce)_N〈(Pr)_N≈(Nd)_N with Eu/Eu~*〉1,and the vein calcite displays(La)_N〉(Ce)_N〉(Pr)_N〉(Nd)_N with Eu/Eu~*〉1.The REE geochemistry of the three types of calcite is different from those of the strata of various age and Permian Emeishan basalt exposed in the orefield.Theδ^(13) C_(PDb) andδ^(18)O_(Smow) values of the three types of calcites vary from-3.5‰to-2.1‰and 16.7‰to 18.6‰,respectively,falling within a small field between primary mantle and marine carbonate in theδ^(13)C_(PDb) vsδ^(18)O_(Smow) diagram. Various lines of evidence demonstrate that the three types of calcites in the deposits are produced from the same source with different stages.The ore-forming fluids of the deposits resulted from crustal -mantle mixing processes,in which the mantle-derived fluid components might be formed from degassing of mantle or/and magmatism of the Permian Emeishan basalts,and the crustal fluid was mainly provided by carbonate strata in the orefield.The ore-forming fluids in the deposits were homogenized before mineralization,and the ore-forming environment varied from relatively reducing to oxidizing.
基金supported by the National Basic Research Program(No.2009CB421008)the Fundamental Research Funds for the Central Universities (No.2010ZY02)+2 种基金China Postdoctoral Science Foundation (No.20090460400)Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT)the 111 Project(No.B07011)
文摘The western margin of Yangtze Craton is known as a significant sediment-hosted base-metal aggregate cluster,especially for Pb-Zn deposits in China,e.g.Jinding,Daliangzi,Tianbaoshan, Kuangshanchang and Qinlinchang deposits.In comparison with the classic MVT deposits in the world, based on the basic geology of the sediment-hosted Pb-Zn deposits,this paper focuses on temporal-spatial distribution of this deposit to further discuss its large scale mineralization and tectonic evolution history.In the SW Sanjiang Thethys,Jinding deposit is typically thrust fault-controlled and hosted mainly in the sandstones and breccia-bearing sandstones,whereas MVT-type deposits are controlled by lithology and faulting/fracturing with a strong preference for carbonate-hosted rocks.Most importantly,Jinding Pb-Zn deposit differs from the other types of sediment-hosted Pb-Zn deposits in which it was formed in a strongly deformed foreland basin within a continental collision zone.In the Kangdian area,the sediment-hosted Pb-Zn deposits were formed in the extensional basin on the side of the continental orogenic belt along the Yangtze Craton.Compared with classic MVT deposits,the Pb-Zn deposits in the Kangdian area belong to MVT deposits.This paper is significant not only for interpretation of the genesis of sediment-hosted Pb-Zn deposits but also for exploiting large base metal deposits in large sedimentary target areas.
基金the Chinese Academy of Sciences (No. KXCX2-109) National Natural Science Foundation of China (No. 40304007 ,No.40172036)+1 种基金"Key Project of Science and Technology Research”(No. 01037) China Postdoctoral Science Foundation (No. 2003033238).
文摘Seventy-three large-superlarge deposits in China were formed in 4 metallogenic epochs, and located in 6 metallogenic domains. By combing their time-space distribution and the relevant data of crustal thickness, we discuss the control conditions of deep tectonics on superlarge deposits. The various spatial variation of the crustal thickness where deposits locate is closely related to their different tectonic setting. The crustal thickness of the region where deposits are in the Precatnbrian metallogenic epoch is 37.1 km and shows double-peak distribution, which is related to the different tectonic-mineralization processes in the Tarim-North China and Yangtze metallogenic domains. The crustal thickness of the region where deposits are in the Paleoproterozoic metallogenic epoch is 43.4 km and shows normal distribution, which is the result of 'pure' mineralization setting. The crustal thickness of the region where deposits are in the Late Palaeozoic-Early Mesozoic metallogenic epoch is about 41.2 km and shows multi-peak distribution, which can be related with dispersing distribution in the metallogenic domain of these superlarge deposits. The crustal thickness of the region where deposits are in the post-Indosinian metallogenic epoch is 37.3 km, and shows skew distribution, which resulted from different tectonic settings in eastern and western China.